Names for the planet Jupiter in ancient Egyptian: Ḥr tЗš tЗwy “Horus-Limits-of-the-Two-Lands, Horus-Who-Encircles-the-Two-Lands,” Ḥr wpš tЗwy “Horus-Who-Illuminates-the-Two-Lands,” and Ḥr wp štЗ “Horus-Opener-of-the-Mystery, Horus-Revealer-of-Secrets” (VYGUS Egyptian Dictionary).

Ancient Egyptian tЗš “boundary, limits” > Sahidic Coptic tōš, toš “boundary, nome” (used in place-name ntoš)[1] > Egyptian-Arabic ṭwš, ṭāš,[2] possibly originally referring to ritual circuit of temple in imitation of circuit of Sun.[3]

[1] Crum, Coptic Dictionary, 452b; see Erman & Grapow, Woerterbuch, V, 235.

[2] Behnstedt & Woidich, Ägyptisch-arabischen Dialekte, IV:293, V:383.

[3] C. J. Bleeker, Egyptian Festivals, 70,85; E. F. Wente, “Egyptian Religion,” in Freedman, ed., Anchor Bible Dictionary, II:409; Budge, Gods of the Egyptians, I:171; Budge, Book of the Dead (1960), 360 n. 2.